Use of combination of anti-PD-1 antibody and VEGFR inhibitor in preparation of drug for treating cancers

ABSTRACT

Disclosed is the use of a combination of an anti-PD-1 antibody and a VEGFR inhibitor in the preparation of a drug for treating cancers.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 16/339,819, filed Apr. 5, 2019 (now allowed), which claims the benefit of International Application No. PCT/CN2017/105410, filed Oct. 9, 2017, which was published in the Chinese language on Apr. 19, 2018, under International Publication No. WO 2018/068691 A1, which claims priority under 35 U.S.C. § 119(b) to Chinese Application No. 201610884688.3, filed Oct. 10, 2016. The disclosure of each of these prior applications is incorporated herein by reference in its entirety.

REFERENCE TO SEQUENCE LISTING SUBMITTED ELECTRONICALLY

This application contains a sequence listing that is submitted electronically via EFS-Web as an ASCII formatted sequence listing with a file name “065825-91US2 Sequence Listing” and a creation date of Oct. 21, 2021, and having a size of 7.28 kb. The sequence listing submitted via EFS-Web is part of the specification and is herein incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to the use of a combination of an anti-PD-1 antibody and a VEGFR inhibitor in the preparation of a medicament for the treatment of cancer.

BACKGROUND OF THE INVENTION

PD-1 antibodies specifically recognize and bind to PD-1 on the surface of lymphocytes, which leads to the blockade of PD-1/PD-L1 signaling pathway. This in turn activates the immune cytotoxicity of T cells against tumors and modulates the immune system of the body to eliminate tumor cells in vivo. WO201508584 discloses a novel anti-PD-1 antibody, which is currently in clinical trials and has shown an anti-tumor effect.

Apatinib is the first oral anti-angiogenic drug for advanced gastric cancer in the world, which is highly selective for VEGFR-2 and has a potent anti-angiogenic effect. In a multicenter, randomized, double-blind, placebo-controlled phase III clinical trial of apatinib in patients with metastatic gastric/gastroesophageal junction cancer after receiving second line therapy, the results showed that, when compared with placebo, apatinib alone could prolong median overall survival by 1.8 months, median progression-free survival by 0.8 months, and adverse events were controllable (Randomized, Double-Blind, Placebo-Controlled Phase III Trial of apatinib in Patients With Chemotherapy-Refractory Advanced or Metastatic Adenocarcinoma of the Stomach or Gastroesophageal Junction. J Clin Oncol, 2016 Feb. 16). The structural formula of apatinib is as shown in formula (I).

CN101676267A discloses a series of salts of apatinib, such as mesylate, hydrochloride, and the like. The pre-clinical animal experiments disclosed in CN101675930A also show that apartinib combined with cytotoxic drugs such as oxaliplatin, 5-Fu, docetaxel and doxorubicin can significantly improve the therapeutic effect.

At present, no combinational use of a PD-1 antibody and a VEGFR inhibitor has been approved for marketing, but multiple PD-1 antibodies (from other companies) and VEGFR inhibitors (such as sunitinib, sorafenib, etc.) are in phase II/III clinical trial, and the indications are respectively malignant liver cancer (sorafenib combined with PD-1 antibody) and metastatic renal cell carcinoma (sunitinib combined with PD-1 antibody). The preliminary results showed that the combinations of two drugs are more effective and better than the single drug.

WO2015119930 discloses the use of a PD-1 antibody in combination with axitinib, and WO2015088847 discloses the use of a PD-1 antibody in combination with pazopanib. However, the action mechanism of these VEGFR inhibitors, including sorafenib, sunitinib, axitinib and pazopanib, differ from that of apatinib. Apatinib has the strongest inhibitory effect on VEGFR-2, but it has little or no inhibition on other kinases, that is, apatinib is highly selective for VEGFR-2. Therefore, the disease treated by apatinib is also different from the aforementioned drugs, and whether apatinib can synergize with a PD-1 antibody and improve its efficacy need to be further studied. In addition, according to a current clinical study of a PD-1 antibody administered alone (Phase I study of the anti-PD-1 antibody SHR-1210 in patients with advanced solid tumors. (2017): e15572-e15572), the incidence of capillary hemangioma was as high as 79.3%, the incidence of hypothyroidism was 29.3%, the incidence of pruritus was 19.0%, and the incidence of diarrhea was 10.3%. Such high incidence of adverse effects undoubtedly put a burden on the mental health and quality of life of cancer patients; therefore, it is very important to reduce adverse effects during drug administration.

SUMMARY OF THE INVENTION

The present invention provides use of a combination of an anti-PD-1 antibody and a VEGFR inhibitor in the preparation of a medicament for the treatment of cancer.

Preferably, the VEGFR inhibitor is a VEGFR-2 inhibitor.

A preferred VEGFR inhibitor of the present invention is a VEGFR inhibitor which has an IC50 of less than 100 nM for VEGFR kinase and has no inhibitory activity against EGFR, HER2, FGFR (IC50>10000 nM), according to the test method disclosed in CN101676267A. A particularly preferred VEGFR inhibitor is a VEGFR-2 inhibitor having an IC50 of less than 50 nM for VEGFR-2 kinase, preferably less than 20 nM, more preferably less than 10 nM, and most preferably less than 5 nM, and the inhibitory effect thereof on VEGFR-1 or VEGFR-3 is poor, for example, its IC50 is greater than 20 nM, preferably greater than 50 nM.

In a preferred embodiment of the present invention, the VEGFR-2 inhibitor is apatinib or a pharmaceutically acceptable salt thereof.

The anti-PD-1 antibody is known, and preferably the light chain variable region of the anti-PD-1 antibody comprises LCDR1, LCDR2 and LCDR3 as shown in SEQ ID NO: 4, SEQ ID NO: 5 and SEQ ID NO: 6, respectively.

The heavy chain variable region of the anti-PD-1 antibody comprises HCDR1, HCDR2 and HCDR3 as shown in SEQ ID NO: 1, SEQ ID NO: 2 and SEQ ID NO: 3, respectively.

Wherein the CDR sequences described above are shown in the following table:

Name Sequence NO. HCDR1 SYMMS SEQID NO: 1 HCDR2 TISGGGANTYYPDSVKG SEQID NO: 2 HCDR3 QLYYFDY SEQID NO: 3 LCDR1 LASQTIGTWLT SEQID NO: 4 LCDR2 TATSLAD SEQID NO: 5 LCDR3 QQVYSIPWT SEQID NO: 6

Preferably, the anti-PD-1 antibody is a humanized antibody.

The preferred humanized antibody light chain sequence is the sequence as shown in SEQ ID NO: 8 or a variant thereof; the variant preferably has 0-10 amino acid substitution(s) in the light chain variable region; more preferably, has the amino acid change of A43 S.

The humanized antibody heavy chain sequence is the sequence as shown in SEQ ID NO: 7 or a variant thereof; the variant preferably has 0-10 amino acid substitution(s) in the heavy chain variable region; more preferably, has the amino acid change of G44R.

Particularly preferred, the humanized antibody light chain sequence is the sequence as shown in SEQ ID NO: 8, and the heavy chain sequence is the sequence as shown in SEQ ID NO: 7.

The sequences of the aforementioned humanized antibody heavy and light chains are as follows:

Heavy chain SEQ ID NO: 7 EVQLVESGGGLVQPGGSLRLSCAASGFTFSSYMMSWVRQAPGKGLEWVA TISGGGANTYYPDSVKGRFTISRDNAKNSLYLQMNSLRAEDTAVYYCAR QLYYFDYWGQGTTVTVSSASTKGPSVFPLAPCSRSTSESTAALGCLVKD YFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKT YTCNVDHKPSNTKVDKRVESKYGPPCPPCPAPEAAGGPSVFLFPPKPKD TLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKPREEQFNS TYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQ VYTLPPSQEEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPP VLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNHYTQKSLSLSL GK Light chain SEQ ID NO: 8 DIQMTQSPSSLSASVGDRVTITCLASQTIGTWLTWYQQKPGKAPKLLIY TATSLADGVPSRFSGSGSGTDFTLTISSLQPEDFATYYCQQVYSIPWTF GGGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQ WKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEV THQGLSSPVTKSFNRGEC

In a preferred embodiment of the present invention, the VEGFR inhibitor can also be selected from the group consisting of MP-0250, DE-120, ALN-VSP, Aflibercept, Anecortave, BI-695502, Bevacizumab, PF-06439535, Carboxyamidotriazole, Vanucizumab, RG-7716, Bevacizumab analogue, Navicixizumab, Ranibizumab, Ranibizumab analogue, Conbercept, IBI-302, BI-836880, ARQ-736, RPI-4610, LMG-324, PTC-299, ABT-165, AG-13958, Brolucizumab, PAN-90806, Vatalanib, ODM-203, Altiratinib, TG-100572, OPT-302, TG-100801, CEP-7055, TAS-115, Ilorasertib, Foretinib, JNJ-26483327, Metatinib, R-1530, Tafetinib, Vorolanib, Donafenib, Subutinib, Regorafenib, VGX-100, ENMD-2076, Anlotinib, Ningetinib, Tesevatinib, Tanibirumab, Lucitanib, Cediranib, Chiauranib, IMC-3C5, Glesatinib, KRN-633, Icrucumab, PF-337210, RAF265, Puquitinib, SU-014813, Tivozanib, Fruquintinib, Sitravatinib, Pegaptanib, Pazopanib, Vandetanib, Axitinib, Sulfatinib, Ramucirumab, Plitidepsin, Orantinib, Alacizumab pegol, Telatinib, Ponatinib, Cabozantinib, Lenvatinib, Brivanib Alaninate, and Linifanib.

In the use of the present invention, the cancer is preferably a cancer expressing PD-L1; more preferably is breast cancer, lung cancer, gastric cancer, intestinal cancer, renal cancer, liver cancer, melanoma, or non-small cell lung cancer; most preferably is non-small cell lung cancer, melanoma and kidney cancer, or intestinal cancer, and the intestinal cancer includes colon cancer, colorectal cancer, and the like.

Apatinib is preferably administered in the form of pharmaceutically acceptable salt when being administered. The pharmaceutically acceptable salt can be selected from the group consisting of mesylate and hydrochloride.

Specifically, when being administered, the anti-PD-1 antibody can be administered at a dose of 0.5-30 mg/kg, preferably 2-10 mg/kg, more preferably 2-6 mg/kg, and most preferably 3 mg/kg It can be administered once every 1 to 3 weeks, preferably once every 2 weeks. For adult humans, a fixed dose can also be used, for example 100-1000 mg per administration, preferably 200-600 mg. The dose of the VEGFR inhibitor can be 3-200 mg/kg. For adult humans, a fixed dose can also be used, for example 100-1000 mg, 250-1000 mg, preferably 400-850 mg, 100-500 mg, it can be administered once per day.

In the present invention, the term “combination” is a mode of administration, including various situations, in which two drugs are administered sequentially or simultaneously. Herein, so-called “simultaneously” refers to the administration of the anti-PD-1 antibody and the VEGFR inhibitor during the same administration cycle. For example, administration of the two drugs within 2 days or within 1 day. So-called “sequentially” administrated includes the administration of the anti-PD-1 antibody and the VEGFR inhibitor in different administration cycles, respectively. These modes of administration all belong to the combination administration described in the present invention.

In a preferred embodiment of the present invention, the anti-PD-1 antibody is administered by injection, for example, subcutaneously or intravenously, and the anti-PD-1 antibody is formulated in an injectable form prior to injection. A particularly preferred injectable form of the anti-PD-1 antibody is injection or a lyophilized powder comprising the anti-PD-1 antibody, buffer, stabilizer, and optionally comprising surfactant. The buffer can be selected from one or more of acetate, citrate, succinate and phosphate. The stabilizer can be selected from sugars or amino acids, preferably disaccharide such as sucrose, lactose, trehalose and maltose. The surfactant is selected from the group consisting of polyoxyethylene hydrogenated castor oil, glycerin fatty acid ester, polyoxyethylene and sorbitan fatty acid ester; preferably the polyoxyethylene sorbitan fatty acid ester is polysorbate 20, 40, 60 or 80; most preferred is polysorbate 20. The most preferred injectable form of the anti-PD-1 antibody comprises anti-PD-1 antibody, acetate buffer, trehalose and polysorbate 20.

The present invention provides the anti-PD-1 antibody as described above in combination with the VEGFR as described above, as a medicament for treating tumors.

The present invention provides the anti-PD-1 antibody as described above in combination with the VEGFR as described above as a medicament for reducing adverse effect of drugs. Preferably, the adverse effect of drugs is selected from the effect caused by the anti-PD-1 antibody or the VEGFR inhibitor.

The present invention provides the anti-PD-1 antibody as described above in combination with the VEGFR inhibitor as described above, as a medicament for reducing the dose of the anti-PD-1 antibody administered alone and/or the dose of the VEGFR inhibitor administered alone.

The present invention provides a method for treating tumors/cancer comprising administering to a patient the anti-PD-1 antibody as described above and the VEGFR inhibitor as described above.

The present invention provides a method for reducing the dose of either the anti-PD-1 antibody or the VEGFR inhibitor administered alone, comprising administering to a patient the anti-PD-1 antibody as described above in combination with the VEGFR inhibitor as described above.

Preferably, when administered in combination with the anti-PD-1 antibody, the VEGFR inhibitor is administered at a dose of 10% to 100%, preferably 10% to 75%, more preferably 75%, 50%, 25%, 12.5% of the dose administered alone.

Preferably, when administered in combination with the VEGFR inhibitor, the anti-PD-1 antibody is administered at a dose of 10% to 100%, preferably 10% to 50% of the dose administered alone.

In a preferred embodiment of the present invention, when the anti-PD-1 antibody is administered in combination with the VEGFR inhibitor, the adverse effect of drugs mediated by the anti-PD-1 antibody and/or the immune system can be reduced; preferably, the adverse effect is selected from the group consisting of a vascular-associated adverse effect, glandular hypofunction, skin adverse effect, respiratory system adverse effect, liver-associated adverse effect, endocrine-associated adverse effect, digestive system adverse effect, kidney-associated adverse effect, fatigue, and pyrexia. The preferred vascular-associated adverse effect is selected from the group consisting of hemangioma, vasculitis, and lymphangioma; the glandular hypofunction is selected from the group consisting of hypothyroidism, hypoparathyroidism, pancreatic hypofunction, and prostatic hypofunction; the skin adverse effect is selected from the group consisting of pruritus, urticaria, rash, and toxic epidermal necrosis; the respiratory adverse effect is selected from the group consisting of pneumonia, bronchitis, chronic obstructive pulmonary disease, and pulmonary fibrosis; the liver-associated adverse effect is selected from the group consisting of hepatitis and liver dysfunction; the endocrine-associated adverse effect is selected from the group consisting of diabetes type I, diabetes type II, and hypoglycemia; the kidney-associated adverse effect is selected from the group consisting of nephritis and renal failure; the digestive system adverse effect is selected from the group consisting of diarrhea, nausea, emesis, enteritis, and constipation. More preferably, the adverse effect of drugs is selected from the group consisting of hemangioma, hypothyroidism, hypoparathyroidism, pruritus, pneumonia, hepatitis, liver dysfunction, diabetes type I, nephritis, and renal failure.

The present invention provides a pharmaceutical kit or a pharmaceutical package, comprising the VEGFR inhibitor and the anti-PD-1 antibody as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 . Effect of administration of antibody and compound on the relative volume of MC38 (PD-L1) xenograft in tumor-bearing mice.

FIG. 2 . Effect of administration of antibody and compound on body weight of tumor-bearing mice with MC38 (PD-L1) xenograft, wherein * indicates p<0.05, vs blank control group.

FIG. 3 . Effect of administration of antibody and compound on MC38 (PD-L1) xenograft in tumor-bearing mice—tumor weight.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is further described below in conjunction with the examples. These examples are not intended to limit the scope of the present invention.

Example 1: Effect of the Anti-PD-1 Antibody and Apatinib Mesylate, Administered Alone or in Combination, on Human PD-1 Transgenic C57 Mice which Bear Mouse Colon Cancer Cell MC-38 (PD-L1) Xenograft Transferred with PD-L1 Gene

1. Study purposes: Human PD-1 transgenic mice were used as test animals. The effects of anti-PD-1 antibody in combination with apartinib on human PD-1 expressed in transgenic C57 mice were evaluated, and the transgenic mice bear mouse colon cancer cell MC-38 (PD-L1) xenograft transfected with PD-L1 gene.

2. Test antibodies and compounds: The anti-PD-1 antibody was prepared according to the method disclosed in WO2015085847 in which the corresponding code of the antibody is H005-1, and the sequences of the heavy and light chain are shown in SEQ ID NO: 7 and SEQ ID NO: 8 in the present invention. Lot number: P1512, 200 mg/vial, formulated into 20 mg/ml before use. Apatinib mesylate was prepared according to the method disclosed in CN101676267A, lot number: 668160401; molecular weight: 493.58; purity: 99.60%.

3. Experimental animals: Human PD-1 transgenic C57 mice, specific-pathogen-free (SPF), with different body weights, 50% male and 50% female, were purchased from IsisInnovation Limited, UK.

4. Drug preparation: Anti-PD-1 antibody (3 mg/kg): anti-PD-1 antibody stock solution (20 mg/ml) was adjusted to a concentration of 0.3 mg/ml with phosphate buffered saline (PBS), and the intraperitoneal injection volume was 0.2 ml/mouse.

Apatinib (200 mg/kg): 400 mg apatinib was dissolved in 20 ml of 0.5% sodium carboxymethylcellulose (NaCMC), adjusted to 20 mg/ml, and was administered in 0.2 ml per mouse by gavage.

The solvent vehicle (HIgG) control contained human IgG (3 mg/kg dissolved in 0.5% CMC, adjusted to 0.3 mg/ml, and the volume for intraperitoneal injection was 0.2 ml/mouse.

5. Test method:

-   -   5.1 C57 mice were adapted to the laboratory environment for >5         days.     -   5.2 Tumor cells transplantation: Skin preparation was performed         on human PD-1 transgenic C57 mice one day before MC38 (PD-L1)         cells (5×10⁶/mouse) were inoculated subcutaneously at the right         flank on June 12. The tumors were then grown for 8 days. When         the tumors reached 142.17±13.30 mm³, the animals were randomly         assigned to 4 groups (d0) with 8 mice in each group (four male         mice and four female mice in each group).     -   5.3 Dose and method of administration: Anti-PD-1 antibody was         injected intraperitoneally, Q2D*7 (once every 2 days, 7 times in         total), and apatinib was administered by oral gavage, QD*14         (once a day for 14 days). The specific drug administration         regimen is shown in Table 1.     -   5.4 Determination of volume of xenograft and body weight of         mice: Tumor volume and body weight were measured twice a week         and data were recorded.     -   5.5 Statistics: Excel 2003 statistical software was used: the         mean was calculated by avg; the SD value was calculated by         STDEV; the SEM value was calculated by STDEV/SQRT; the P value         indicating the difference between groups is calculated by TTEST.         The formula for calculating tumor volume (V) is:         V=½×L _(long) ×L _(short) ²         Relative volume (RTV)=V _(T) /V ₀         Tumor inhibition rate (%)=(C _(RTV) −T _(RTV))/C _(RTV)(%)         Wherein, V₀ and V_(T) are the tumor volume at the beginning of         the experiment and at the end of the experiment, respectively.         C_(RTV) and T_(RTV) are the relative tumor volumes of the blank         control group and the experimental group at the end of the         experiment, respectively.

6. Test results: The PD-1 antibody was injected intraperitoneally, Q2D*7, and compound apatinib was administered by oral gavage, QD*14. On day 21 after the initial administration, the tumor inhibition rate of the group administered with the anti-PD-1 antibody (3 mg/kg) alone was 20.40%, and the tumor inhibition rate of the group administered with apatinib (200 mg/kg) alone was 35.67%. The tumor inhibition rate of the combination of the anti-PD-1 antibody (3 mg/kg) and apatinib (200 mg/kg) was 63.07% (significantly different from that in human IgG control group) There were no significant differences between the other administration groups (administration of agent alone) relative to the human IgG control group. From the experimental results, the efficacy of the combination group of the anti-PD-1 antibody (3 mg/kg)+apatinib (200 mg/kg) is superior to that of the anti-PD-1 antibody administrated alone and that of apintinib administrated alone. The body weight of mice in each group was normal, indicating that the drug had no obvious side effects. The specific data are shown in Table 1 and FIGS. 1-3 .

Example 2: Clinical Study of Anti-PD-1 Antibody Combined with Apatinib Mesylate in the Treatment of Advanced Malignant Tumor

Inclusion criteria: (1) advanced malignancy; (2) failure in chemotherapy by using first-line, second-line or above; (3) measurable lesions; (4) ECOG score 0-1.

Test drugs: commercially available apatinib mesylate tablet; the anti-PD-1 antibody of Example 1.

Method of administration: Up to Sep. 20, 2017, a total of 31 subjects were screened, 30 subjects were enrolled (14 subjects withdrew from treatment, and 16 subjects were still in the group of administration).

Administration method for subjects No. 001-005 was intravenous infusion of anti-PD-1 antibody, 3 mg/kg, once every 2 weeks; apatinib orally, 500 mg, once a day. Administration method for subjects No. 006-010 was intravenous infusion of anti-PD-1 antibody, 200 mg, once every 2 weeks; apatinib orally, 125 mg, once a day. Administration method for subjects No. 011-031 was intravenous infusion of anti-PD-1 antibody, 200 mg, once every 2 weeks; apatinib orally, 250 mg, once a day.

Clinical Outcome: In terms of effectiveness, in the 6^(th) week, there were 24 evaluable data for efficacy evaluation, with a disease control rate (DCR) of 83.3% (20/24); in the 12th week, there were 19 evaluable data for efficacy evaluation, with a DCR of 63.2% (12/19); in the 18th week, there were 10 evaluable data for efficacy evaluation, with a DCR of 70% (7/10); in the 24th week, there were 5 evaluable data for efficacy evaluation, with a DCR of 80% (4/5); up to Sep. 20, 2017, there were 2 hepatocellular carcinoma subjects with their 24-week effect of partial response (PR) and progression-free survival (PFS) of more than 6 months. Among the 24 evaluable data, there were 4 cases showing optimal efficacy with PR, 15 cases of stable disease (SD), and 5 cases of progressive disease (PD). Although the objective response rate (ORR) was only 16.7%, the DCR was high, e.g., as high as 79%, and some subjects had a PFS of more than 6 months. The specific results are shown in Table 2, Table 3 and Table 4. In addition, the dose of apatinib alone in treatment of solid tumor (such as gastric cancer, gastroesophageal junction adenocarcinoma, liver cancer, etc.) was usually up to 850 mg/day (see instructions for apatinib). However, in embodiments of the invention the combination of apatinib and anti-PD-1 antibody makes it possible to reduce the dose of apatinib down to 125 mg/day, and provides improved effectiveness and better safety when compared with apatinib administrated alone. In terms of safety, up to September 20, 11 cases of serious adverse events (SAE) were reported in 8 subjects, and the incidence of SAE was 26.7% (8/30). Seven of the SAEs were observed in subjects No. 001-005 (wherein the dose of apatinib for initial test was high, 500 mg) and accounted for most of the serious adverse events. However, with modified dosage regimen, it was found that good anti-tumor effect could be maintained, and the adverse effects caused by high dose of apintinib could be significantly reduced. In addition, in this clinical study it was surprisingly found that the combination of apatinib and anti-PD-1 antibody showed almost no hemangioma-associated adverse effect in the treatment of malignant tumors when compared with anti-PD-1 antibody alone. Hemangiomas was observed in only one subject who was administrated with PD-1 antibody alone, due to intolerance to combination therapy.

Example 3: Phase II Clinical Study of Anti-PD-1 Antibody Combined with Apatinib Mesylate in the Treatment of Advanced Non-Small Cell Lung Cancer

Inclusion criteria: (1) advanced non-small cell lung cancer; (2) failure in chemotherapy by using first-line or second-line or above; (3) measurable lesions; (4) ECOG score 0-1.

Test drugs: commercially available apatinib mesylate tablet; the anti-PD-1 antibody of Example 1.

Method of administration: Anti-PD-1 antibody, once every 2 weeks, intravenous infusion, 200 mg each time; apatinib mesylate orally, once daily, 250 mg or 375 mg or 500 mg each time.

Clinical results: up to July 28, a total of 15 subjects were screened, of which 12 were enrolled. A total of 12 subjects completed at least 1 cycle of administration observation, 10 patients (10/12) had disease in stable condition, and 1 patient had partial remission. See Table 5 for details. Surprisingly, it was found that the combination of apatinib mesylate and anti-PD-1 antibody enhanced the efficacy and reduced the adverse effects when compared with anti-PD-1 antibody administered alone. In this study, the common adverse effects were usually grade I to II, and the incidence of anti-PD-1 antibody-associated or immune-associated adverse effects (such as capillary hemangioma) was only 8% (1 case), the incidence of hypothyroidism was only 8% (1 case), and gastrointestinal adverse effects (such as diarrhea) and skin adverse effect (such as pruritus) were not observed. In an ASCO report published in 2017, anti-PD-1 antibody administrated alone for the treatment of solid tumors in phase I clinical trial exhibited an incidence of capillary hemangioma as high as 79.3%, and the incidence of hypothyroidism was 29.3%, the incidence of pruritus was 19.0%, the incidence of diarrhea was 10.3% (Phase I study of the anti-PD-1 antibody SHR-1210 in patients with advanced solid tumors. (2017): e15572-e15572). Therefore, the combination of apatinib mesylate and anti-PD-1 antibody can not only alleviate or control the tumor proliferation of non-small cell lung cancer (which has experienced chemotherapy failure), but also reduce the anti-PD-1 antibody-associated or immune-mediated adverse effects and improve the life quality of patients.

TABLE 1 Number Mean tumor volume Mean tumor volume Relative tumor % Tumor of (mm³) (mm³) volume inhibition P animals/ Group Administration Route D 0 SEM D 21 SEM D 21 SEM rate D 21 (vs blank) group HIgG (3 mg/kg) Q2D*7 ip 141.46 13.23 1983.55 292.09 14.41 2.07 — — 8 Anti-PD-1 antibody Q2D*7 ip 146.40 12.68 1652.93 309.61 11.47 2.49 20.40% 0.379164 8 (3 mg/kg) Anti-PD-1 antibody (3 Q2D*7/ ip/po 146.11 11.69 771.95 73.42 5.32 0.73 63.07%** 0.001007 8 mg/kg) + apatinib QD(14 D) (200 mg/kg) apatinib QD(14 D) po 139.70 7.59 1263.86 206.54 9.27 1.58 25.67% 0.068923 8 **p < 0.01, vs control group

TABLE 2 Administration methods: PD-1 antibody 3 mg/kg + apatinib 500 mg Previous Treatment 6 weeks 12 weeks 18 weeks 24 weeks 32 weeks Optimal No. Diagnosis therapy cycle evaluation evaluation evaluation evaluation evaluation efficacy 001 gastric cancer Second-line 1 NA NA NA NA NA Not evaluated therapy 002 gastric cancer Fouth-line 6 SD reduced PD NA NA NA SD therapy 003 gastric cancer Fifth-line 9 SD reduced SD reduced PD PD NA SD therapy 004 hepatocellular First-line 2 SD increased NA NA NA NA SD carcinoma therapy 005 hepatocellular Second-line 1 NA NA NA NA NA Not evaluated carcinoma therapy

TABLE 3 Administration methods: PD-1 antibody 200 mg + apatinib 125 mg Previous Treatment 6 weeks 12 weeks 18 weeks 24 weeks 32 weeks Optimal No. Diagnosis therapy cycle evaluation evaluation evaluation evaluation evaluation efficacy 006 hepatocellular Second-line 18 SD increased SD increased PD PR SD PR carcinoma therapy 007 hepatocellular Second-line 18 SD SD reduced SD reduced SD Performed, SD carcinoma therapy Not evaluated 009 hepatocellular Second-line 18 SD SD reduced SD reduced SD reduced NA SD carcinoma therapy 008 hepatocellular First-line 4 PD NA NA NA NA PD carcinoma therapy 010 gastric cancer Third-line 2 NA NA NA NA NA Not evaluated therapy

TABLE 4 Administration methods: PD-1 antibody 200 mg + apatinib 250 mg Treatment 6 weeks 12 weeks 18 weeks 24 weeks 32 weeks Optimal No. Diagnosis Therapy cycle evaluation evaluation evaluation evaluation evaluation efficacy 011 hepatocellular Second-line 15 SD reduced PR PR PR NA PR carcinoma therapy 014 hepatocellular Third-line 14 SD reduced SD reduced SD Performed, NA SD carcinoma therapy Not evaluated 019 hepatocellular Second-line 11 SD SD reduced SD NA NA SD carcinoma therapy 021 hepatocellular First-line 9 SD increased SD Performed, NA NA SD carcinoma therapy Not evaluated 027 hepatocellular Second-line 3 SD reduced Not performed NA NA NA SD carcinoma therapy 018 hepatocellular Second-line 4 SD increased PD NA NA NA PD carcinoma therapy 016 gastric cancer Fouth-line 9 PR PD PD NA NA PR therapy 025 gastric cancer Second-line 8 PR PR NA NA NA PR therapy 012 gastric cancer Multi-line 9 SD reduced SD reduced SD increased NA NA SD therapy 013 gastric cancer Third-line 5 SD NA NA NA NA SD therapy 022 gastric cancer Second-line 10 SD reduced SD SD NA NA SD therapy 024 gastric cancer Third-line 6 SD increased PD NA NA NA SD therapy 026 gastric cancer Third-line 8 SD reduced SD NA NA NA SD therapy 028 gastric cancer Third-line 7 SD Performed, NA NA NA SD therapy Not evaluated 015 gastric cancer Second-line 5 9 weeks PD PD NA NA NA PD therapy 017 gastric cancer Fifth-line 4 PD PD NA NA NA PD therapy 023 gastric cancer Second-line 5 PD PD NA NA NA PD therapy 029 gastric cancer Multi-line 5 Performed, NA NA NA NA To be therapy Not evaluated evaluated 030 gastric cancer Third-line 5 Performed, NA NA NA NA To be therapy Not evaluated evaluated 031 gastric cancer Second-line 3 Not NA NA NA NA Not evaluated therapy Performed

TABLE 5 Efficacy evaluation of enrolled patients Screening Efficacy evaluation-Diameter(mm)/Baseline ratio (%) General No. Baseline 2 cycles 4 cycles evaluation 01001 28   27/−3.6% 15.5/−44.6% PR 01002 20.6    1 cycle, PD hydrothorax increased 01003 76.7 New onset of hydrothorax 74.7/−2.6% SD 01005 122.9 liver metastases increased, PD enlarged 01006 137   118/−13.9%  107/−22% SD 01007 134.2 117.7/−12.2%  107/−20.3 SD 01008 58.3   52/−10.8% SD SD 01010 11    9/−20% SD 01011 36 SD SD 01013 87 SD SD 01014 85.5 SD SD 01015 SD SD 

We claim:
 1. A method for treating cancer in a subject in need thereof, the method comprising administering to the subject, an anti-PD-1 antibody and apatinib or a pharmaceutically acceptable salt thereof, wherein the anti-PD-1 antibody comprises: an antibody light chain variable region comprising LCDR1, LCDR2 and LCDR3 having the amino acid sequences of SEQ ID NO: 4, SEQ ID NO: 5 and SEQ ID NO: 6, respectively; and an antibody heavy chain variable region comprising HCDR1, HCDR2 and HCDR3 having the amino acid sequences of SEQ ID NO: 1, SEQ ID NO: 2 and SEQ ID NO: 3, respectively, wherein the apatinib or the pharmaceutically acceptable salt thereof is administered orally at a dose from 125 mg to 375 mg.
 2. The method of claim 1, wherein the pharmaceutically acceptable salt of apatinib is mesylate salt of apatinib or hydrochloride salt of apatinib.
 3. The method of claim 1, wherein the anti-PD-1 antibody is a humanized antibody.
 4. The method of claim 3, wherein the humanized antibody comprises an antibody light chain variable region having the amino acid sequence of SEQ ID NO: 8 or a SEQ ID NO: 8 mutant sequence having 1 to 10 amino acid substitutions in SEQ ID NO: 8, and an antibody heavy chain variable region having the amino acid sequence of SEQ ID NO: 7 or a SEQ ID NO: 7 mutant sequence having 1 to 10 amino acid substitutions in SEQ ID NO:
 7. 5. The method of claim 1, wherein the antibody light chain variable region comprises the amino acid sequence of SEQ ID NO: 8 and the antibody heavy chain variable region comprises the amino acid sequence of SEQ ID NO:
 7. 6. The method of claim 4, wherein the antibody light chain variable region comprises a mutant sequence of the amino acid sequence of SEQ ID NO: 8 having the amino acid substitution A43S, and the antibody heavy chain variable region comprises a mutant sequence of the amino acid sequence of SEQ ID NO: 7 having the amino acid substitution G44R.
 7. The method of claim 1, wherein the cancer is selected from the group consisting of breast cancer, lung cancer, liver cancer, gastric cancer, intestinal cancer, renal cancer, melanoma and non-small cell lung cancer.
 8. The method of claim 7, wherein the subject has failed at least one chemotherapy prior to the administration of the anti-PD-1 antibody and apatinib or the pharmaceutically acceptable salt thereof.
 9. The method of claim 1, wherein the anti-PD-1 antibody is administered at a dose of 2 mg/kg to 6 mg/kg body weight of the subject or from 100 mg to 1000 mg per administration.
 10. The method of claim 9, wherein the anti-PD-1 antibody is administered at a dose from 200 mg to 600 mg per administration.
 11. The method of claim 1, wherein the anti-PD-1 antibody is administered at a dose of 3 mg/kg body weight of the subject or 200 mg once every 1 to 3 weeks.
 12. The method of claim 1, wherein the anti-PD-1 antibody is administered at a dose of 3 mg/kg body weight of the subject or 200 mg once every two weeks.
 13. The method of claim 1, wherein the apatinib or the pharmaceutically acceptable salt thereof is administered orally at a dose of 125 mg, 250 mg, or 375 mg.
 14. The method of claim 1, wherein the apatinib or the pharmaceutically acceptable salt thereof is administered orally at said dose of 125 mg to 375 mg once daily.
 15. The method of claim 1, wherein the anti-PD-1 antibody is administered at a dose of 3 mg/kg body weight of the subject or 200 mg.
 16. The method of claim 1, wherein the anti-PD-1 antibody is administered at a dose of 3 mg/kg body weight of the subject or 200 mg once every 1 to 3 weeks, and the apatinib or the pharmaceutically acceptable salt thereof is administered orally at said dose from 125 mg to 375 mg once daily.
 17. The method of claim 1, wherein the anti-PD-1 antibody is administered at a dose of 3 mg/kg body weight of the subject or 200 mg once every two weeks, and the apatinib or the pharmaceutically acceptable salt thereof is administered orally at a dose of 250 mg or 375 mg once daily. 